Two types of intraoral distribution of fluorotic enamel

Abstract Different distributions of fluorotic dental enamel within the dentition have been described in the literature. This report describes two patterns of intraoral distribution. In nine Tanzanian low fluorosis communities with a prevalence of pitting fluorosis of less than 2% and in live moderate fluorosis communities with a prevalence of pitting fluorosis of 16–59%, incisors and first molars were the least affected teeth. In four high fluorosis communities with a prevalence of pitting fluorosis of 86–97%, maxillary incisors exhibited lower Thylstrup-Fejerskov Index values than the maxillary canines, premolars and molars. The mandibular teeth exhibited increasing Thylstrup-Fejerskov Index values from the anterior to the posterior region. The curves presenting the intraoral distribution of the severity of dental fluorosis corresponded with the curve presenting the completion time of primary enamel formation of the various tooth types, with the exception of the first molars in high fluorosis communities. The similarity of the curves suggests that the later in life enamel is completed, the higher is the severity of dental fluorosis. This relation seems to be explained by the prevailing feeding and dietary habits, which result in minimal intake of fluoride in the first 18 months of life during breastfeeding, followed by increasing fluoride ingestion in the following years through consumption of tea, seafish and F-containing magadi salt.     

A global perspective on changes in the burden of caries and periodontitis: implications for dentistry

The structure and contents of most oral health care systems and the contents of dental curricula reflect a deep-rooted tradition for attempting to cure oral diseases by refined technological means. However, better oral health conditions for the world's populations necessitate the application of up-to-date scientific knowledge to control the major oral diseases. This review points out that not only should the structure and contents of oral health care delivery systems be based on state-of-the-art knowledge about the biology of the oral diseases; they must also take into account the trends for change in caries and periodontal diseases within and between populations, and acknowledge the impact of changes in treatment philosophies for these trends. The oral disease profiles for populations in low- and high-income countries are briefly described, and it is concluded that the rapidly changing disease profiles observed in high-income countries necessitate re-thinking of the future role and organization of dentistry in such countries. The priorities for low- and middle-income countries must be to avoid repeating the mistakes made in the high-income countries. Instead, these societies might take advantage of setting priorities based on a population-based common risk factor approach. If such an approach is adopted, the training of personnel with oral health care competence must be rethought. The authors suggest three different cadres of dental care providers to be considered for an approach that allows health care planners in different populations around the world to prioritize appropriate oral health care with due respect for the socio-economic conditions prevailing.     

Total viable count and differential count of vibrio (campylobacter) sputorum, fusobacterium nucleatum, selenomonas sputigena, bacteroides ochraceus and veillonella in the inflamed and non inflamed human gingival crevice

From 3 groups of individuals with non inflamed, slightly inflamed or moderately inflamed gingiva 3 to 4 paperpoint samples were taken from different buccal gingival crevices in each individual.
Samples were cultivated on a modified CBRCA medium which permitted the differential count of five groups of gram-negative anaerobes. The total count per volume units was 9-times higher in moderately inflamed than in non inflamed crevices. A significant increase in the proportion of Vibrio (Campylobacter) sputorum and Fusobacterium nucleatum occurred with inceasing gingival index score. Bacteroides ochraceus and Selenomonas sputigena , though present in low numbers also increased slightly. The proportion of Veillonella seemed independent of gingival index score. This added up to a significant increase in the proportion of cultivable gram-negative organisms with increasing gingival index score.     

Immunobiological consequence of regulation of insulin receptor on alloactivated lymphocytes in normal and obese subjects

Acute manipulations of insulin in vivo regulate the display of insulin receptors induced on activated T lymphocytes after presentation of alloantigen. This study explored the immunobiological consequences of regulation of insulin-receptor display by acute manipulations of insulin achieved during the hyperinsulinemic-euglycemic clamp in healthy normal individuals and obese subjects. T lymphocytes were isolated at 0, 1, and 4 h of hyperinsulinemia from seven normal volunteers and seven obese individuals and studied for their capacity to 1) synthesize a complement of insulin receptors on cell membrane, 2) respond to alloantigen in the mixed-lymphocyte culture (an immunologic activity unrelated to manipulations in insulin concentrations in complete medium), and 3) respond to the lymphocyte-mediated cytotoxicity reaction (an immunologic activity known to be modulated by insulin). In the face of a reduction in receptor numbers to 25% of baseline in normal individuals, alloreactivity in the mixed-lymphocyte culture was not affected (95 +/- 9% of time 0 after 4 h of hyperinsulinemia), whereas lymphocyte-mediated cytotoxicity fell from 14 +/- 4 at time 0 to 2 +/- 2% sp Cr release (P less than 0.02). Hyperinsulinemia achieved by the clamp in seven obese subjects did not alter the synthesis of insulin receptors on cell membrane after presentation of alloantigen. In the absence of further reduction of insulin-receptor membrane display, neither the mixed-lymphocyte culture nor lymphocyte-mediated cytotoxicity reaction was affected. It is concluded that those immunologic activities of lymphocytes that can be modulated by insulin are affected by regulation of insulin-receptor display on activated lymphocytes. Therefore, receptor regulation is not effete but carries significant immunologic consequence.(ABSTRACT TRUNCATED AT 250 WORDS)     

Is antibiotic therapy justified in the treatment of human chronic inflammatory periodontal disease?

New insight into the possible involvement of specific bacteria in the etiology of periodontal disease has stimulated interest in antibiotic therapy. However, current knowledge does not allow the designation of one or more pathogens in periodontal diseases. Some bacteria are considered suspected periodontal pathogens due to their predominance in the pocket and their potential pathogenicity, yet they all appear to be indigenous bacteria. For this reason, one can question the rationale for the use of antibiotics in the treatment of periodontal disease since the theoretical basis for their application seems small. Several reports of clinical trials in which antibiotics were administered as an adjunct to scaling and rootplaning in adult periodontitis conclude with encouraging statements concerning bacterial inhibition and the cure of inflammatory periodontal disease. However, the data are conflicting and mostly negative. Antibiotic treatment in combination with scaling and rootplaning in juvenile periodontitis and refractory adult periodontitis has shown some benefit, but the clinical trials were not sufficiently controlled to permit conclusions. So far, antibiotics have been applied as a last resort in order to supplement the non-specific approach of mechanical root debridement, but it can be doubted whether this approach offers any benefit in the long run.